[13C12]Dibenzofuran, 1.2ml x 50ug/ml, toluene

Total Kjeldahl Nitrogen as N

84 µS/cm calibration solution (230mL)

Sulfur Calibration Mixtures: Di-n-butyl sulfide in Heavy White Oil (less than 20mg/kg S) Unit : 10mL screw-capped bottle Light White Mineral Oil Heavy White Mineral Oil (20 cSt at 40°C) (70 cSt at 40°C)